1. Field of the Invention
The present invention relates to a particulate filter for an internal combustion engine and a method for producing the same.
2. Description of the Related Art
A particulate filter for trapping particulates contained in exhaust gas exhausted from an internal combustion engine is disclosed in the official gazette of JP-T-8-508199. This particulate filter is provided with a plurality of exhaust gas flow passages defined by partitions. According to the technique disclosed in this official gazette, the partitions defining the exhaust gas flow passages are made of porous material. An opening of each exhaust gas flow passage on the upstream side and an opening of each exhaust gas flow passage on the downstream side are alternately closed, and thus exhaust gas can flow out from the filter after the exhaust gas has passed through the partitions.
In this connection, in the particulate filter disclosed in the above official gazette, the partitions in the opening regions of the exhaust gas flow passages are deformed so that they can approach each other and the forward end portions of these partitions are connected with each other, and thus the openings of the exhaust gas flow passages are closed. In the case where the openings of the exhaust gas flow passages are closed in this way, the partitions can be easily deformed when a quantity of deformation of the partitions to close the openings of the exhaust gas flow passages is small. In general, it is preferable that the mechanical strength of the particulate filter is high.
It is an object of the present invention to reduce a quantity of deformation of partitions, to close openings of exhaust gas flow passages of a particulate filter, as much as possible. It is also an object of the present invention to enhance the mechanical strength of a particulate filter as much as possible.